A variety of systems have been developed for forming images of the surface of the earth or other planetary bodies from an aircraft or a spacecraft. Such systems have proven highly useful in the performance of mapping and surveillance functions, as well as in the unmanned exploration of planetary bodies in the solar system.
The fidelity of the images produced by such systems is significantly influenced by perturbations in the movement of the vehicle carrying the system and various techniques have already been proposed for eliminating, or at least minimizing, the adverse influences of such perturbations on the fidelity of the resulting images. These efforts have included techniques for stabilizing the support for the imaging system, the derivation of a record of such perturbations, and various correlation techniques for comparing images obtained at different points in time.
Attempts to correct for all perturbations which may be experienced by the observation system according to techniques known in the art would require the provision of an extremely large number of sensor elements, a correspondingly large memory and complex logic. Indeed, the quantity of data generated by such an arrangement would prevent the resulting data from being processed or transmitted in real time.